/**
 * Copyright (C) 2007 The AsyncMail Group <asyncmail@googlegroups.com>
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *         http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.googlecode.asyncmail.smtpserver.handler.fastfail;

import org.apache.commons.logging.Log;
import org.springframework.beans.factory.annotation.Required;

import com.googlecode.asyncmail.common.DSNStatus;
import com.googlecode.asyncmail.common.MailEnvelope;
import com.googlecode.asyncmail.smtpserver.SMTPSession;
import com.googlecode.asyncmail.smtpserver.hook.HookResult;
import com.googlecode.asyncmail.smtpserver.hook.HookReturnCode;
import com.googlecode.asyncmail.smtpserver.hook.MessageHook;
import com.googlecode.asyncmail.util.streamscanner.StreamScanner;

/**
 * Abstract class which a handler should extend if a StreamScanner is used to
 * scan the message
 * 
 */
public abstract class AbstractStreamScannerHandler implements MessageHook {

    private Log logger;

    private StreamScanner scanner;

    @Required
    public void setLogger(Log logger) {
        this.logger = logger;
    }

    protected Log getLogger() {
        return logger;
    }

    public void initialize() {
        scanner = getStreamScanner();
    }

    /**
     * @see com.googlecode.asyncmail.smtpserver.hook.MessageHook#onMessage(com.googlecode.asyncmail.smtpserver.SMTPSession,
     *      com.googlecode.asyncmail.common.MailEnvelope)
     */
    public HookResult onMessage(SMTPSession session, MailEnvelope mail) {

        String result = scanner.scan(mail.getBodyInputStream());

        if (result != null) {
            return new HookResult(HookReturnCode.DENY, DSNStatus.getStatus(
                    DSNStatus.PERMANENT, DSNStatus.SECURITY_OTHER)
                    + " Message blocked. " + result);
        }

        return new HookResult(HookReturnCode.DECLINED);
    }

    /**
     * Return the StreamScanner to use
     * 
     * @return StreamScanner
     */
    protected abstract StreamScanner getStreamScanner();
}
